How to troubleshoot no serial communication on Watlow Control Unit?
- SSydney ShawAug 25, 2025
To resolve a 'No Serial Communication' issue with your Watlow Control Unit, ensure that each device on the network has a unique address. Verify that the protocol, baud rate, and parity settings match between all devices. Check for any wiring issues and inspect or replace the converter if needed. Ensure the communication port is correctly set up and that the software setup matches the controller's configuration. Keep communication wires away from power wires and place a 120 Ω resistor across EIA-485 on the last controller.












